Disclaimer: I do not own Supernatural, which means its characters, recognized locations, or lore. I just have a bit of fun.
The realization that Dean loved Castiel didn't set his heart racing, cause fireworks to go off, or hit him like a freight train. No. Instead, it felt safe and familiar, like slipping into his old leather jacket. It was something, Dean realized, that he had been existing within him without him having the words for it. It felt natural, as though it had always been that way, and Dean supposed it kind of had been. A tiny smile appeared on his face as he recalled his and Cas' "profound bond".
Dean's initial misgivings concerning Castiel had quickly diminished and formed into wary trust. That trust solidified into friendship, crossed to family, and then melted into love.
They had been through a lot. Between dangerous hunts, the Apocalypse, the demons, the war in Heaven, and the Leviathans, Dean supposed Purgatory had been the catalyst. That year… They had been fighting for their lives with no end in sight, the mere rumor of a way out their only hope. But that wasn't what had kept him fighting. He had fought for Cas. He fought first to find him and then to keep him safe. Cas safe. Even then, it had been all he needed, all he wanted, for peace of mind. Even in that hellish place, with Cas beside him, as he should be, everything was okay.
And then Cas had purposefully stayed behind and it had broken Dean. He had carried on as best he could, blaming himself all the while, but Sam had known what was wrong all the same. He was still mourning his Archangel, Gabriel. He had understood the pain Dean refused to let out. The guilt ate at him, rising from his subconscious as horrible nightmares that then followed him to the waking world. He saw Cas everywhere, haunting him as he continued to grind himself into the dust. He waited for something, anything, to happen. And it had. Cas returned and Dean had inwardly rejoiced. He had looked into Cas' crystal blue eyes and felt himself be pulled back together. After all, Cas had rebuilt him once before as Dean was raised from Hell.
Dean moved his hand to cover the mark on his shoulder with care. Castiel's mark. His hand print would forever be etched into Dean's skin and now, Dean wouldn't have it any other way. Everything he had done or said had led him to this conclusion, this moment.
"Dean?"
Cas' gruff voice, tired with sleep, brought Dean out of his reverie. He turned from his seat before the TV where he had been attempting to watch Raiders of the Lost Ark to look at Cas standing in the doorway, rubbing his eyes. He was wearing his pajama pants with bees on them that Sam had found and bought for him, and an old grey t-shirt that had, at one point, been Dean's.
Dean looked over Cas' sleepy form, smiling fondly, "Yeah, Cas?"
He shuffled forward and plopped himself on the couch next to Dean.
"I woke up," he stated, yawning while staring blankly as Indiana Jones ran from a boulder.
Dean chuckled, muted the TV, and nudged the sleepy Angel, "Yeah, I see that. You alright?"
Castiel's eyes flicked to Dean's and he nodded stiffly, "Yes. I simply had, what you would call, a nightmare. It was…new. And unpleasant."
Dean grimaced in sympathy. He'd had his fair share of nightmares, but for Cas, whose Grace was steadily slipping away, it would be unfamiliar territory. Cas' nightmares would no doubt be bad for a while.
Deciding not to pry, and in true Winchester fashion, Dean let it drop, saying instead, "Why don't you stay out here and watch the movie? It'll take your mind off stuff."
Cas tipped his head in acquiescence, curling his feet beneath him and relaxing deeper into the couch with a sigh. Dean grabbed the remote and un-muted the movie before settling in himself.
Three quarters of the way through Raiders, Cas' head had migrated to Dean's left shoulder as the Angel snored lightly. Dean didn't mind, especially after his epiphany, but after a few minutes, the positioning of Cas' head began to get uncomfortable.
Slowly, Dean moved to the right and gently brought Cas down to lay with his head on Dean's lap. The Angel instantly moved to grasp onto Dean's shirt and buried his face into the warmth of Dean's stomach. Chuckling softly, Dean brought his arm up to lightly brush his fingers through Cas' perpetually messy hair. Cas mumbled something in his sleep and cuddled closer while Dean smiled tenderly down at his Angel as he stroked Cas' dark locks.
Glancing up after a while and seeing the movie credits onscreen, Dean turned off the TV. The low light from the kitchen of the bunker played across Cas' cheekbones, softening his features. In sleep, Castiel looked peaceful. As cliché as it was, Dean thought he looked like an Angel as he had originally imagined them; forgiving beings full of light and love, like his mother had once told him. It was something he would never tell Sammy, but he had also been disappointed when most of the Angels turned out to be bent on destruction or constantly vying for power. Castiel, Gabriel, and Samandriel had been the only Angels who weren't interested in such things. And now, two of those three were dead while the first was losing his Grace with no way of getting it back. And they had looked. God, they had looked. He and Sam, alright mostly Sam, had scoured the library in the bunker and every source and contact they could think of, but to no avail. Cas had said it was alright, but Dean knew it wasn't. How could it be? Soon, Castiel wouldn't be an Angel anymore. He would be human. And like every human, Cas would be vulnerable. No longer safe…
Dean stiffened and froze, his fingers still tangled in Castiel's hair. No. No, no, no.
His breathing sped up slightly, and Dean forced himself to remain calm as to not wake up the Angel sleeping on his thigh. He continued running his hand over Cas' hair as he silently chanted that Cas would be safe. Cas was safe. He was here and Dean would take care of him. Everything would be…
"Dean?"
Cas' voice was muffled by Dean's shirt, but Dean heard him all the same.
Dean slowly moved his hand from Cas' head and he could've sworn he heard Cas whine a little before the Angel turned his head enough to see Dean properly.
"Did I miss Indiana Jones?" he asked quietly, voice once again heavy with sleep as he blinked lazily at Dean.
"Nah, it's fine. You need rest more than a movie marathon," he paused uncertainly for a moment before continuing, "Come on. Let's get you to bed." Dean began shifting so he could stand.
This time, Cas definitely whined, "I do not wish to move. I will stay on the couch."
Dean rolled his eyes as he stood and watched the Angel bury his head back into the space Dean had just vacated.
"Seriously, Cas. That won't be comfortable in the morning."
A grunt, "I do not care."
Dean huffed, amused, reached out to roll Cas back over and, without letting himself think about what he was doing, picked Cas up and cradled the sleepy man to his chest.
Castiel shifted, latched onto the front of Dean's shirt, and buried his face into the space between Dean's neck and shoulder before breathing in deeply through his nose and relaxing almost completely into Dean's arms.
Dean moved towards the hallway leading to Cas' room and thought about how if Sam saw this, he would never let Dean live it down. Dean already knew he would forever be dealing with a cackling barrage of "I told you so" if Castiel returned Dean's feelings. Even if he didn't, Sam wasn't wrong about Dean himself. Dean sighed heavily at the thought of the impending annoyance that was his little brother.
The movement must have jostled Castiel, since he lifted his head slightly in confusion before registering where he was and who was carrying him. Without questioning Dean, Cas laid his head back onto Dean's shoulder as Dean crossed the final bit of distance to Cas' bedroom. Thankfully, Cas had left his door open, so Dean was able to maneuver into the room with no trouble.
Dean smirked as he noticed that Cas still hadn't quite grasped the concept of decorating, but the Angel had picked out his own bedding, so that was something.
Closing the door softly with his foot and crossing to the bed, Dean gingerly laid Cas down onto his pillows and covered him so he wouldn't be cold. The bunker had its advantages, but good heating at night was not one of them. So, for good measure, Dean also grabbed up the blanket laying across the end of Cas' bed and placed it over the Angel before turning to head to his own room. He didn't expect to be stopped by a hand on his wrist. Nor did he expect Cas' quiet voice to break the silence with the simple call of his name.
"What is it, Cas?" The hand on him disappeared. When Dean turned around again, he saw his Angel staring up at him with wide blue eyes. Eyes that held traces of fear. Dean's heart pulled a little at the look and he sat next to Cas on the bed, his hand automatically running over Cas' hair in comfort. Dean knew he wasn't acting like he normally did, but he figured Cas was either too tired to notice or simply didn't mind the change. Dean was hoping for the latter.
When Cas didn't answer, Dean asked again, softer this time, "What is it, Cas?"
The Angel blinked and looked away towards the space behind Dean before whispering, "Stay with me?" Cas quickly glanced back toward Dean, eyes searching his face while he tried to gauge Dean's reaction to the question.
The hesitancy of the request was obvious in both the Angel's voice and in the way Cas had tensed beneath his blankets. Dean knew he could never tell his Angel no, so he squeezed Cas' arm, feeling the Angel relax into the touch, before standing and removing his jeans. Left only in his boxers and a t-shirt, Dean quietly slipped into the space Cas had just moved from to make room for him under the covers. Cas was still staring at him.
After a few rather tense moments, Dean sighed in utter resignation and opened his arms for Cas to slide into. Cas, with almost no hesitation, moved forward and cuddled as close to Dean as he could get. Dean folded him into his embrace a moment later and tucked Cas' head beneath his chin and held him.
With his Angel snugly pressed against him, legs entangled, and Cas' hands once more grasping the front of his shirt, Dean smiled softly before giving in and lightly kissing Cas' forehead.
"Yeah, Cas. I'll stay with you."